Fabriken



UNITED STATES PATENT @rricE.

MARTIN HERZBERG, OF ELBERFELD, GERMANY, ASSIGNOR TO THE FABBEN-FABRIKEN, VORMALS FR. BAYER & COMPANY, OF SAME PLACE.

MANUFACTURE OF DYE-STUFFS.

SPECIFICATION forming part of Letters Patent No. 88%,31 dated u 12, 1888Application filed February 21, 1888. Serial No. 264,832. (Spceimensd ToaZZ whom it may concern.-

Be it known that I, llIARTIN HERZBERG, doctor ofphilosophy, a subject ofthe Emperor ofGermany, and residing at Elberfeld, assignor to theFarbenfabriken, vorrnals Fr. Bayer 85 Company, have invented a newanduseful Improvement in the lllanut'acture of Dye-Stuffs orColoring-limiters, of which the following is a specification.

lliyinvcntion relates to the production of new brown coloringnnatter fordyeing cotton, wool, and silk by the action ofdiazo compound ofnaphthylaniine sulpho-acid on the coloring matter well known in commerceunder the name ol"Bisinarck brown, (triamidoazo-ben- 201 ortllillllldOHZO-tOlllOi.)

For carrying out my process practically, I proceed as follows: 8.5 kilosof naphthylamine sulphonic acid are converted in the wellknown mannerinto the muriatic diazo compound. The solution of the same is slowly,under continuous stirring, poured into a solution containing forty kilosof Bismarck brown. After having (settled) stood for about twelve hours,the mixture is made alkaline by a carbonate of alkali and heated. Abrown solution is formed, which, after filtration, is precipitated bycommon salt. After some time, filter and dry. The dye stuff thusobtained 0 forms in a dry state a brown powder, which is easily solublein water and dyes not mordantcd cotton in a boiling alkaline or soapbath a splendid brown color which will not be altered by acetic acid.Sill; and wool can be dyed with the same result in a boiling bath of 5 Acommon salt. On adding mineral acid to the aqueous solution the freeacid of the dye-stuff will be formed, which is insoluble in water, whilealkali will not alter the product. with concentrated sulphuric acid thedyestuft' de- 0 scribed dissolves into a dirty violet powder.

I do not claim in this application the process described, intending tomake a separate application.

That I claim as my invention, and desire to 5 secure by Letters Patent,is

Thehrown coloringmatter herein described, which has the followingcharacteristics: it exists as a brown powder easily soluble in water,dyes cotton, wool, and silk a splendid brown in a boiling bath of commonsalt, cotton likewise in a boiling alkaline or soap bath, which colorwill not be altered by acetic acid; by adding muriatic acid to theaqueous solution the free acid of the dye-stuff is formed; with con- 5 5centrated sulphuric acid the dye stuff described dissolves into a dirtyviolet-brown color- In testimony whcrcofl havesigued myname to thisspecification in the presence of two wit- 6o messes.

MARTIN HERZBERG.

Witnesses:

ANTON KEUTER, OTTO KRAUSE.

